title: Effect of mannitol on cerebrovascular pressure reactivity in patients with intracranial hypertension.
abstract: OBJECTIVE
  Mannitol is commonly used in patients with increased intracranial pressure (ICP), but its effect on cerebrovascular pressure reactivity (CVPR) is uncertain. We analyzed the changes of pressure reactivity index (PRx) during the course of mannitol treatment.
  
  
  METHODS
  Twenty-one patients who received mannitol treatment for increased ICP were recruited prospectively. Continuous waveforms of arterial blood pressure (ABP) and ICP were collected simultaneously for 60 minutes (10 minutes at baseline and 50 minutes since mannitol administration) during 37 events of mannitol treatment. The correlation coefficients between the mean ABP and ICP were averaged every 10 minutes and labeled as the PRx. The linear correlation of six time points of PRx in each event was calculated to represent the trend of CVPR changes. The negative slope of correlation was defined as improvement in CVPR under mannitol treatment and vice versa.
  
  
  RESULTS
  At baseline, the average of ICP was 26.0 ± 9.1 mmHg and the values of PRx were significantly correlated with ICP (p = 0.0044, r = 0.46). After mannitol administration, the average of ICP decreased significantly to 21.2 ± 11.1 mmHg (p = 0.036), and CVPR improved in 59.4 % of all events. Further analysis showed that low baseline cerebral perfusion pressure was the only hemodynamic parameter significant association with the improvement of CVPR after mannitol treatment (p = 0.039).
  
  
  CONCLUSIONS
  Despite lowering ICP, mannitol may have diverse effects on CVPR in patients with intracranial hypertension. Our study suggests that mannitol infusion may have a beneficial effect on CVPR, particularly in those with a low cerebral perfusion pressure at baseline.
authors.affiliation: Stroke Center and Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan; NTU-NTUH-MediaTek Innovative Medical Electronics Research Center, Taipei, Taiwan.
authors.forename: Sung-Chun
authors.initials: SC
authors.lastname: Tang
authors.affiliation: Stroke Center and Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ru-Jen
authors.initials: RJ
authors.lastname: Lin
authors.affiliation: Department of Mechanical Engineering, Yuan Ze University, Tao-Yuan, Taiwan.
authors.forename: Jiann-Shing
authors.initials: JS
authors.lastname: Shieh
authors.affiliation: NTU-NTUH-MediaTek Innovative Medical Electronics Research Center, Taipei, Taiwan; Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: An-Yeu
authors.initials: AY
authors.lastname: Wu
authors.affiliation: NTU-NTUH-MediaTek Innovative Medical Electronics Research Center, Taipei, Taiwan; Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Dar-Ming
authors.initials: DM
authors.lastname: Lai
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan; National Taiwan University Hospital, Jin-Shan Branch, Taipei, Taiwan. Electronic address: sjhuang1@ntu.edu.tw.
authors.forename: Sheng-Jean
authors.initials: SJ
authors.lastname: Huang
authors.affiliation: Stroke Center and Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan. Electronic address: jsjeng@ntu.edu.tw.
authors.forename: Jiann-Shing
authors.initials: JS
authors.lastname: Jeng
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000503:physiopathology; D001930:Brain Injuries / Q000150:complications*; D005260:Female; D006706:Homeostasis; D006801:Humans; D019586:Intracranial Hypertension / Q000188:drug therapy*; D007427:Intracranial Pressure / Q000187:drug effects*; D008297:Male; D008353:Mannitol / Q000008:administration & dosage*; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies
chemical_list: D008353:Mannitol
keywords: cerebral perfusion pressure; cerebrovascular pressure reactivity; intracranial hypertension; mannitol